Methods of making microelectronic assemblies including compliant interfaces

• US 7,368,818 B2
• Filed: 10/26/2005
• Issued: 05/06/2008
• Est. Priority Date: 09/20/1994
• Status: Expired due to Fees

• Current Assignee: Tessera, Inc. (Adeia Inc.)
• Original Assignee: Tessera, Inc. (Adeia Inc.)
• Inventors: Smith, John W., Kovac, Zlata, Mitchell, Craig S., DiStefano, Thomas H.
• Primary Examiner(s): Zarneke; David A.
• Application Number:
  US11/259,398
• Publication Number:
  US 20060049498A1
• Time in Patent Office: 923 Days
• Field of Search: 257/735
• US Class Current: 257/735
• CPC Class Codes: H01L 21/56 Encapsulations, e.g. encapsulation layers, coatings
• CPC Class Codes: H01L 21/563 Encapsulation of active face of flip-chip device, e.g. underfilling or underencapsulation of flip-chip, encapsulation preform on chip or mounting substrate
• CPC Class Codes: H01L 21/565 Moulds
• CPC Class Codes: H01L 2224/16 of an individual bump connector
• CPC Class Codes: H01L 2224/73203 Bump and layer connectors
• CPC Class Codes: H01L 2224/81 using a bump connector
• CPC Class Codes: H01L 2224/81136 involving guiding structures, e.g. spacers or supporting members
• CPC Class Codes: H01L 2224/81801 Soldering or alloying
• CPC Class Codes: H01L 2224/83136 involving guiding structures, e.g. spacers or supporting members
• CPC Class Codes: H01L 2224/83192 wherein the layer connectors are disposed only on another item or body to be connected to the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/83194 Lateral distribution of the layer connectors
• CPC Class Codes: H01L 2224/97 the devices being connected to a common substrate, e.g. interposer, said common substrate being separable into individual assemblies after connecting
• CPC Class Codes: H01L 23/3114 the device being a chip scale package, e.g. CSP
• CPC Class Codes: H01L 23/49811 Additional leads joined to the metallisation on the insulating substrate, e.g. pins, bumps, wires, flat leads H01L23/49827 takes precedence
• CPC Class Codes: H01L 23/49816 Spherical bumps on the substrate for external connection, e.g. ball grid arrays [BGA]
• CPC Class Codes: H01L 23/49827 Via connections through the substrates, e.g. pins going through the substrate, coaxial cables H01L23/49822, H01L23/49833, H01L23/4985, H01L23/49861 take precedence
• CPC Class Codes: H01L 23/4985 Flexible insulating substrates H01L23/49572 and H01L23/49855 take precedence
• CPC Class Codes: H01L 24/29 of an individual layer connector
• CPC Class Codes: H01L 24/72 Detachable connecting means consisting of mechanical auxiliary parts connecting the device, e.g. pressure contacts using springs or clips
• CPC Class Codes: H01L 24/81 using a bump connector
• CPC Class Codes: H01L 24/97 : the devices being connected to a common substrate, e.g. interposer, said common substrate being separable into individual assemblies after connecting
• CPC Class Codes: H01L 2924/00 : Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/01005 : Boron [B]
• CPC Class Codes: H01L 2924/01006 : Carbon [C]
• CPC Class Codes: H01L 2924/01013 : Aluminum [Al]
• CPC Class Codes: H01L 2924/01027 : Cobalt [Co]
• CPC Class Codes: H01L 2924/01033 : Arsenic [As]
• CPC Class Codes: H01L 2924/01082 : Lead [Pb]
• CPC Class Codes: H01L 2924/01322 : Eutectic Alloys, i.e. obtained by a liquid transforming into two solid phases
• CPC Class Codes: H01L 2924/014 : Solder alloys
• CPC Class Codes: H01L 2924/15153 : the die mounting substrate comprising a recess for hosting the device
• CPC Class Codes: H01L 2924/15165 : Monolayer substrate
• CPC Class Codes: H01L 2924/15311 : being a ball array, e.g. BGA
• CPC Class Codes: H01L 2924/1532 : the connection portion being formed on the die mounting surface of the substrate
• CPC Class Codes: H01L 2924/16152 : Cap comprising a cavity for hosting the device, e.g. U-shaped cap
• CPC Class Codes: H01L 2924/19041 : being a capacitor
• CPC Class Codes: H01L 2924/19043 : being a resistor
• CPC Class Codes: H01L 2924/351 : Thermal stress
• CPC Class Codes: H01L 2924/3512 : Cracking
• CPC Class Codes: H05K 1/118 : specially for flexible printed circuits, e.g. using folded portions
• CPC Class Codes: H05K 2201/0133 : Elastomeric or compliant polymer
• CPC Class Codes: H05K 2201/0394 : Conductor crossing over a hole in the substrate or a gap between two separate substrate parts
• CPC Class Codes: H05K 2201/0397 : Tab
• CPC Class Codes: H05K 2201/09081 : Tongue or tail integrated in planar structure, e.g. obtained by cutting from the planar structure
• CPC Class Codes: H05K 2203/063 : of preperforated insulating layer
• CPC Class Codes: H05K 3/361 : Assembling flexible printed circuits with other printed circuits
• CPC Class Codes: H05K 3/4084 : by deforming at least one of the conductive layers

Abstract

An assembly includes a structure, a plurality of terminals and a plurality of compliant pads disposed between said terminals and said structure. The terminals are aligned with at least some of said pads, with the pads providing a standoff between the structure and the terminals. The compliant pads are preferably made of a non-conductive material such as a silicone elastomer.

Claims

1. An assembly comprising:

(a) a structure;

(b) a plurality of terminals electrically connected to said structure;

(c) a plurality of compliant pads disposed between said terminals and said structure, said terminals being aligned with at least some of said pads, said pads providing a standoff between said structure and said terminals;

(d) a flexible film, said terminals being disposed on said film, said compliant pads being disposed between said film and said structure, said film having a first side facing toward said structure and a second side facing away from said structure, said terminals being exposed at said second side of said film; and

(e) a compliant filler disposed between said compliant pads and between said structure and said flexible film.

2. An assembly as claimed in claim 1 wherein said pads are arranged in a grid pattern.

3. An assembly as claimed in claim 2 wherein said pads are spaced apart from one another so as to define channels between adjacent ones of said pads.

4. An assembly as claimed in claim 3 wherein the center-to-center distance between adjacent ones of said pads is greater than the minimum width of each said pad.

5. An assembly as claimed in claim 3 wherein the center-to-center distance between adjacent ones of said pads is greater than the maximum width of each said pad.

6. An assembly as claimed in claim 1 wherein each said pad has a maximum width between about 300 μ

m and 2000 μ

m.

7. An assembly as claimed in claim 1 wherein each said pad has a ratio of width to height of about two to one (2:

1) or greater.

8. An assembly as claimed in claim 1 wherein said pads are formed from an elastomer.

9. An assembly as claimed in claim 8 wherein said elastomer is a silicone elastomer.

10. An assembly as claimed in claim 1 wherein at least some of said pads are multi-terminal pads, a plurality of said terminals being aligned with each said multi-terminal pad.

11. An assembly as claimed in claim 1 wherein at least some of said pads are single-terminal pads, each said single-terminal pad being aligned with only one of said terminals.

12. An assembly as claimed in claim 1 wherein said pads are of substantially uniform shape and size.

13. An assembly as claimed in claim 1 wherein said pads are of different shapes and sizes.

14. An assembly as claimed in claim 1 wherein said structure is a semiconductor chip having contacts and said terminals are electrically connected to the contacts of said chip.

15. An assembly as claimed in claim 14 further comprising leads extending to contacts on said chip spaced apart from said pads, said terminals being electrically connected to said contacts through said leads.